Who can explain the explort functions of the Wow64 kernel32.dll in Windows 7

There is the disasmmber of the GetFileSize in wow64 kernel32.dll under on Windows 7 x64

.text:7DD7196E ; Exported entry 497. GetFileSize
.text:7DD7196E ; =============== S U B R O U T I N E =======================================
.text:7DD7196E ; Attributes: bp-based frame
.text:7DD7196E ; DWORD __stdcall GetFileSizeStub(HANDLE hFile, LPDWORD lpFileSizeHigh)
.text:7DD7196E public _GetFileSizeStub@8
.text:7DD7196E xxxxx@8 proc near ; DATA XREF: .text:off_7DE1FA20o
.text:7DD7196E hFile = dword ptr 8
.text:7DD7196E lpFileSizeHigh = dword ptr 0Ch
.text:7DD7196E mov edi, edi
.text:7DD71970 push ebp
.text:7DD71971 mov ebp, esp
.text:7DD71973 pop ebp
.text:7DD71974 jmp short _GetFileSize@8 ; GetFileSize(x,x)
.text:7DD71974 ; ---------------------------------------------------------------------------
.text:7DD71976 db 5 dup(90h)
.text:7DD7197B ; ---------------------------------------------------------------------------
.text:7DD7197B ; DWORD __stdcall GetFileSize(HANDLE hFile, LPDWORD lpFileSizeHigh)
.text:7DD7197B _GetFileSize@8: ; CODE XREF: GetFileSizeStub(x,x)+6j
.text:7DD7197B ; BackupGetSparseMap(x,x,x)+3Ap …
.text:7DD7197B jmp ds:__imp__GetFileSize@8 ; GetFileSize(x,x)
.text:7DD7197B xxxxx@8 endp
.text:7DD71981 db 5 dup(90h)